1. Field of the Invention
This invention relates to a valve actuator for regulating the flow of a quarter-turn valve. More specifically, the invention is a valve actuator which departs from the prior art by placing a primary actuating system and a return spring system in a non-collinear manner relative to each other, meaning the primary actuating system and return spring system are no longer exclusively in line with each other.
2. Description of the Related Art
In the past, valve actuators employing a pressure-actuated piston and return spring system placed both systems exclusively in line with one another. As a result, the length of the piston's stroke and displacement of the return spring had a one-to-one correspondence. In other words, a displacement of four inches in the pressure-actuated piston corresponded to four inches of compression in the return spring. Therefore, the weight of return spring systems in valve actuators employing this design remained dependent on the displacement of the pressure actuated piston due to the linear relationship between the two systems. Accordingly, the need to reduce the mass of valve actuators for flight systems resulted in the non-collinear valve actuator.